NEW YORK — NASCAR has undergone significant format modifications this season in an attempt to bolster its reach, but additional major changes are unlikely.

"More tweaks, if any at all are made, they'd be minor because we believe the current format we have is built to stand a long time," NASCAR chairman Brian France said Friday at a conference with sports editors.

NASCAR is 11 races into the 2014 Sprint Cup Series schedule under the new format, which results in a winner-take-all championship race for the first time in its history. The previous format was a 10-race playoff, in which points were given based on finish to determine a champion.

"What I was most concerned with was listening to drivers get out of the car and settling for second, fourth or fifth place," France said. "In the old format, that was a good day, arguably. With all the young drivers that we have coming, that's not the culture of competition we want to have in NASCAR. Our championship is so important. It makes a lot of money and it's obviously the most prestigious motorsports championship, we think, in the world. So understandably, they'll race to whatever format that achieves that goal."

France suggested that the changes to the championship structure has altered the way drivers race, forcing them to increase "taking risks" and being more aggressive in the pursuit of victories, as opposed to securing points.

When weighing safety, however, France didn't indicate that more changes would be likely, despite several calls from drivers to install SAFER barriers that help absorb crash impacts to any parts of racetrack walls that have concrete.

"We're going to put SAFER walls wherever it's necessary," France said. "There are parts of the track that we may determine aren't necessary for those walls. When and if we think they are, we'll obviously make sure that happens. We do add SAFER walls to the inside areas depending on if it's necessary.

"We'll do it wherever it's appropriate. Period. We already have. We've been clear about that. We don't think it's necessary, as an example, to do it on pit lane, because they're not running fast enough and it wouldn't make any sense to do that, so wherever it's appropriate, we'll do it."

Since each race track is different, there are challenges to installing SAFER walls in all places where cars are exposed to concrete. According to France, several factors determine whether or not the barriers are necessary.

"It's determined by where it is on the track," France said. "As I said and as an example, there are no SAFER barriers on pit road, even though there's obviously a crash wall. The vast majority of the speedways in the primary racing surface have SAFER barriers. There might be a gate. There might be something that's inside. Remember, you've got 18 or 19 different speedways, all configured differently, some have very abrupt inside retaining walls for the track. It might be grass, where it's just not going to be necessary to put the SAFER walls in certain places, in our view. But when we do, when it's necessary, we will."

According to France, when NASCAR mandates that a SAFER wall be installed, the respective track is responsible for the cost.

Last month, Denny Hamlin was the latest driver to speak out about the need to install more of the SAFER walls.

"Well they always seek it out," France said. "That's not anything new, one thing or another. Most of the time, we're the ones mandating safety changes and often they don't do it with all safety changes, but they don't always think that each and every one of them are entirely in the right direction, so it's not surprising from time to time that they have different views on that.